Try OpenEdge Now
skip to main content
GUI for .NET Primer
Basic Types of Forms and Application Design : Form inheritance

Form inheritance

GUI for .NET supports inheritance from .NET forms. All of your application-specific forms typically inherit from the Progress.Windows.Form class. You might want to create your own ABL form class and then derive forms from that. This technique is a good idea for enforcing a company standard across all forms in your application. One advantage of putting common behavior in a super class is that feature changes or bug fixes to that class are propagated to all derived classes.
However, putting too much functionality in a super form class might result in having to write workaround code (overrides) in derived forms to get the particular instance behavior you want. So, try to put in a super class only functionality that is required by all derived classes.
OpenEdge applications can support both ABL windows and .NET forms. .NET forms can be mixed with ABL windows in the same application. For Windows desktop applications that already use the OpenEdge GUI, you can add new GUI for .NET forms without changing the ABL windows of the existing user interface. The windows and forms can run side-by-side and one can parent the other. Each window and form is an independent entity in the application.